[LAA] Enable symbolic stride speculation for all LAA clients

This is a functional change for LLE and LDist.  The other clients (LV,
LVerLICM) already had this explicitly enabled.

The temporary boolean parameter to LAA is removed that allowed turning
off speculation of symbolic strides.  This makes LAA's caching interface
LAA::getInfo only take the loop as the parameter.  This makes the
interface more friendly to the new Pass Manager.

The flag -enable-mem-access-versioning is moved from LV to a LAA which
now allows turning off speculation globally.

llvm-svn: 273064

1 files changed, 65 insertions, 0 deletions

diff --git a/llvm/test/Transforms/LoopDistribute/symbolic-stride.ll b/llvm/test/Transforms/LoopDistribute/symbolic-stride.ll
new file mode 100644
index 00000000000..73d3d19c5dd
--- /dev/null
+++ b/llvm/test/Transforms/LoopDistribute/symbolic-stride.ll
@@ -0,0 +1,65 @@
+; RUN: opt -basicaa -loop-distribute -S < %s | \
+; RUN:     FileCheck %s --check-prefix=ALL --check-prefix=STRIDE_SPEC
+
+; RUN: opt -basicaa -loop-distribute -S -enable-mem-access-versioning=0 < %s | \
+; RUN:     FileCheck %s --check-prefix=ALL --check-prefix=NO_STRIDE_SPEC
+
+; If we don't speculate stride for 1 we can't distribute along the line
+; because we could have a backward dependence:
+;
+;   for (i = 0; i < n; i++) {
+;     A[i + 1] = A[i] * B[i];
+;     =======================
+;     C[i] = D[i] * A[stride * i];
+;   }
+
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.10.0"
+
+; ALL-LABEL: @f(
+define void @f(i32* noalias %a,
+               i32* noalias %b,
+               i32* noalias %c,
+               i32* noalias %d,
+               i64 %stride) {
+entry:
+  br label %for.body
+
+; STRIDE_SPEC: %ident.check = icmp ne i64 %stride, 1
+
+; STRIDE_SPEC: for.body.ldist1:
+; NO_STRIDE_SPEC-NOT: for.body.ldist1:
+
+for.body:                                         ; preds = %for.body, %entry
+  %ind = phi i64 [ 0, %entry ], [ %add, %for.body ]
+
+  %arrayidxA = getelementptr inbounds i32, i32* %a, i64 %ind
+  %loadA = load i32, i32* %arrayidxA, align 4
+
+  %arrayidxB = getelementptr inbounds i32, i32* %b, i64 %ind
+  %loadB = load i32, i32* %arrayidxB, align 4
+
+  %mulA = mul i32 %loadB, %loadA
+
+  %add = add nuw nsw i64 %ind, 1
+  %arrayidxA_plus_4 = getelementptr inbounds i32, i32* %a, i64 %add
+  store i32 %mulA, i32* %arrayidxA_plus_4, align 4
+
+  %arrayidxD = getelementptr inbounds i32, i32* %d, i64 %ind
+  %loadD = load i32, i32* %arrayidxD, align 4
+
+  %mul = mul i64 %ind, %stride
+  %arrayidxStridedA = getelementptr inbounds i32, i32* %a, i64 %mul
+  %loadStridedA = load i32, i32* %arrayidxStridedA, align 4
+
+  %mulC = mul i32 %loadD, %loadStridedA
+
+  %arrayidxC = getelementptr inbounds i32, i32* %c, i64 %ind
+  store i32 %mulC, i32* %arrayidxC, align 4
+
+  %exitcond = icmp eq i64 %add, 20
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:                                          ; preds = %for.body
+  ret void
+}